This invention relates to an environmental conditioning system for a vehicle, such as an aircraft.
In flight, an aircraft may obtain conditioned air from a compressor of a turbine engine. Bleed air is output at a high temperature from the compressor and is passed through a heat exchanger to lower the air's temperature. The air eventually passes to the passenger compartment. This process of conditioning air from the compressor is known as an air cycle.
This method of conditioning air is inefficient. More energy than is necessary is used to condition the air because the pressure delivered by the engine compressor exceeds the pressure required for adequate conditioning at most operating points and is throttled away. Generating the unnecessary pressure is inefficient use of power. As a consequence of the inefficiency of the environmental conditioning system, the aircraft consumes more fuel than necessary.
A need therefore exists for more efficient environmental conditioning system for use on an aircraft.